Chamber Angle Research Articles

Secondary Neovascular Glaucoma in the Course of Diabetes in a Kidney Transplant Recipient: Case Report and Review of the Literature

The increase in intraocular pressure during hemodialysis challenges nephrologists and ophthalmologists. It most often affects patients with previously diagnosed glaucoma and is particularly dangerous in the setting of diabetic retinopathy. Hypoperfusion and hypoxia of the retina may occur, leading to pathologic neovascularization in the retina and the anterior chamber angle. Changes in the filtration angle block the outflow of aqueous humor and cause secondary glaucoma. A special type of glaucoma is neovascular glaucoma, developing among others in patients with diabetic retinopathy. This study describes a patient with secondary neovascular glaucoma in whom a significant increase in intraocular pressure was observed during hemodialysis, not responding to the applied topical treatment. The patient experienced severe pain, and her cornea was constantly injured by paracentesis. Ultimately, secondary glaucoma led to a significant decrease in vision in both eyes. The patient was enrolled on a transplant waiting list and transplanted with priority. The patient experienced some urologic and infectious complications, although 7 months after transplantation, her creatinine concentration was 1.2 mg/dL, and the ocular disease was stabilized. The intraocular pressure decreased, but there were still values above the norm, which required periodic injections of anti-vascular endothelial growth factor into the vitreous chamber and 5-fluorouracil injections under the conjunctiva. Patients with diabetes and secondary neovascular glaucoma on dialysis constitute an extremely difficult therapeutic problem and require the involvement of several specialists. Successful kidney transplantation, besides ameliorating general clinical conditions, may increase the chance of successful ophthalmologic treatment.

Anterior Segment Changes in Patients With Glaucoma Following Cataract Surgery.

This prospective observational study investigates the impact of cataract surgery on anterior segment parameters innonglaucomatous and primary open-angle glaucoma (POAG) eyes, utilizing anterior segment optical coherence tomography (AS-OCT). The study involved 42 Caucasian patients, divided into a control group and a POAG group. Comprehensive ophthalmic examinations were performed along with AS-OCT imaging and biometry preoperatively, as well as on one day, one week, and one month following cataract surgery. The results showed significant post-operativechanges in anterior chamber depth (ACD) and angle width in both groups, suggesting that cataract surgery may influence the structural parameters associated with glaucoma risk and management. Specifically, a marked increase in ACD and improvement in angle-opening distances were observed, highlighting the potential of cataract extraction to alter intraocular fluid dynamics favorably. Despite these changes, the study noted an initial spike in increased intraocular pressure (IOP) in POAG patients immediately post-operative, which stabilized during follow-up. For the control group, IOP showed gradually reducing IOP values in the follow-up visits. The findings underscore the role of advanced imaging technologies in understanding glaucoma's pathophysiology and the potential benefits of cataract surgery in glaucoma patients. The study advocates for further research with a larger, more diverse patient population and extended follow-up to explore the long-term implications of cataract surgery on glaucoma dynamics, emphasizing the importance ofpersonalized management and treatment strategies particularly for glaucoma patients.

A Histomorphometric and Computational Investigation of the Stabilizing Role of Pectinate Ligaments in the Aqueous Outflow Pathway.

Murine models are commonly used to study glaucoma, the leading cause of irreversible blindness. Glaucoma is associated with elevated intra-ocular pressure (IOP), which is regulated by the tissues of the aqueous outflow pathway. In particular, pectinate ligaments (PLs) connect the iris and trabecular meshwork (TM) at the anterior chamber angle, with an unknown role in maintenance of the biomechanical stability of the aqueous outflow pathway, thus motivating this study. We conducted histomorphometric analysis and optical coherence tomography-based finite element (FE) modeling on three cohorts of C57BL/6 mice: "young" (2-6 months), "middle-aged" (11-16 months), and "elderly" (25-32 months). We evaluated the age-specific morphology of the outflow pathway tissues. Further, because of the known pressure-dependent Schlemm's canal (SC) narrowing, we assessed the dependence of the SC lumen area on varying IOPs in age-specific FE models over a physiological range of TM/PL stiffness values. We found age-dependent changes in morphology of outflow tissues; notably, the PLs were more developed in older mice compared to younger ones. In addition, FE modeling demonstrated that murine SC patency is highly dependent on the presence of PLs and that increased IOP caused SC collapse only with sufficiently low TM/PL stiffness values. Moreover, the elderly model showed more susceptibility to SC collapse compared to the younger models. In conclusion, our study elucidated the previously unexplored role of PLs in the aqueous outflow pathway, indicating their function in supporting TM and SC under elevated IOP.

Universal slit-lamp mounted indentation gonioscopy tool for angle evaluation: An innovative device.

In the field of ophthalmology, slit-lamp gonioscopy has long been a cornerstone for examining anterior chamber angles and diagnosing conditions such as angle closure, secondary causes of raised intraocular pressure, neovascularization of angle, angle recession, angle tumors, and foreign bodies. However, the conventional approach for goniophotography is a demanding procedure requiring juggling a gonioscopy lens in one hand and a smartphone in the other. Balancing a gonioscopy lens with one hand makes it difficult to adjust and focus the image in busy clinical settings. This article introduces a groundbreaking solution to this problem - a universal slit-lamp-mounted gonioscope ingeniously repurposed from discarded materials, that is, indirect goniophotography (IndiGo). This novel system simplifies the process of both gonioscopy and goniophotography, allowing ophthalmologists to easily assess anterior chamber angles and capture high-quality images. These images can be swiftly shared with glaucoma specialists worldwide for digital analysis. Not only does this approach enhance examination efficiency, but also it fosters sustainability in ophthalmic diagnostics.

Assessing the Impact of Tropicamide on Anterior Segment Parameters in Diabetic Patients: A Randomized Clinical Trial.

Evaluation of anterior segment parameters is crucial in ophthalmic procedures such as intraocular surgeries and contact lens fitting. However, the use of tropicamide in diabetic patients presents challenges due to its potential impact on biometric measurements. This study aims to investigate and compare the effects of 0.5% and 1% tropicamide on anterior segment parameters in diabetic patients. This double-masked randomized clinical trial enrolled 98 patients with diabetes mellitus. Participants were randomly assigned to receive either 0.5% or 1% tropicamide. Anterior segment parameters were measured using Pentacam HR (Oculus Optikgeräte GmbH, Wetzlar, Germany) before and 30 minutes after tropicamide administration. Parameters included anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), keratometry, central corneal thickness (CCT), white-to-white distance (WTW), and pupillary diameter (PD). Both concentrations of 0.5% and 1% tropicamide induced significant changes in anterior segment parameters. There was a notable increase in PD (2.99 ± 0.62, 3.11 ± 0.55, respectively, both P-values < 0.001), ACD (both 0.10 ± 0.05, both P-values < 0.001), ACV (16.69 ± 9.56, 17.51 ± 9.26, respectively, both P-values < 0.001), and WTW (0.06 ± 0.14,0.03 ± 0.30, respectively, both P-values < 0.001), along with a decrease in ACA (-3.50 ± 10.65, -3.30 ± 6.87, P-value< 0.001 and P-value=0.001,respectively), and CCT (-6.10 ± 8.06,-6.39 ± 9.97,respectively, both P-values < 0.001) post-dilation. However, no significant changes were observed in keratometry (front Km (-0.03 ± 0.19, -0.04 ± 0.21, respectively), back Km (0.01 ± 0.05, 0.004 ± 0.05, respectively), P-values> 0.05). Both concentrations of tropicamide exhibited comparable effects on anterior segment parameters in diabetic patients. These post-dilation changes should be considered for accurate intraocular lens power calculation and decision-making for cataract, phakic intraocular lens, and refractive surgeries.

Reverse pupillary block, in contemporary scleral intraocular lens procedures.

To evaluate the frequency and anterior segment optical coherence tomography parameters of patients with scleral fixated intraocular lenses (IOL) and reverse pupillary block (RPB). Retrospective analysis at a tertiary care centre (Department for Ophthalmology and Optometry, Medical University of Vienna, Austria). We researched our records for patients who underwent scleral fixated IOL implantation from January 2018 till February 2023. Patients were included only if there was at least one adequate post-operative scan of anterior segment optical coherence tomography (AS-OCT) available. Initially, AS-OCT scans were assessed for IOL tilt and decentration employing a 3D scan and then later for anterior chamber angle (ACA), aqueous anterior chamber depth (AQD), pupil diameter and iris-IOL distance using the 2D scan at a 0° angle. Both an iris-IOL distance of 0 or less and an ACA of more than 70° were required to define an RPB. A total of 110 patients met the inclusion criteria, 41 were treated using the Carlevale, 33 the four flanged, 24 the Yamane and 12 the Scharioth technique, respectively. RPB was found in 32 patients (29%). Twenty patients with RPB were treated using YAG peripheral iridotomy, mean ACA decreased from 91.91° ± 13.77 to 61.02° ± 8.52, (p < 0.001), mean AQD decreased from 4.67 mm ± 0.47 to 4.31 ± 0.36 mm (p < 0.001) and mean iris-IOL distance increased from -0.09 ± 0.04 to 0.33 ± 0.30 (p < 0.001). RPB is found in a third of eyes who have undergone scleral fixated IOL implantation without iridectomy. YAG peripheral iridotomy is a potent option to treat RPB, and subsequently reduce the risk of iris chafing and secondary inflammation or glaucoma.

Outcome of illuminated microcatheter-assisted circumferential trabeculotomy following failed angle surgery in PAX6 aniridic glaucoma: a case report and literature review

BackgroundAniridia is a rare eye disorder with a high incidence of glaucoma, and surgical intervention is often needed to control the intraocular pressure (IOP). Here, we reported a case of illuminated microcatheter-assisted circumferential trabeculotomy (MAT) performed on an aniridic glaucoma patient following a previous failed angle surgery. The surgical procedures for aniridic glaucoma were also reviewed.Case presentationA 21-year-old man, diagnosed with aniridic glaucoma, came to our hospital consulting for the poor control of left eye’s IOP despite receiving goniotomy surgery 3 years ago. The IOP was 26 mmHg with maximum topical antiglaucoma eyedrops. The central cornea was opaque and the majority of iris was absent. The gonioscopy and ultrasound biomicroscopy (UBM) demonstrated that 360° anterior chamber angle was closed. The whole exome sequencing of peripheral blood confirmed a 13.39 Mb copy number loss at chromosome 11p15.1p13, containing PAX6 and WT1 gene. The 360° MAT surgery was performed on his left eye. At 1-year follow-up, the IOP was 19mmHg with 2 kinds of topical antiglaucoma medications, and the postoperative UBM demonstrated the successful incision of the anterior chamber angle.ConclusionsThe case presented here exhibited a case of aniridic glaucoma treated by MAT surgery. The MAT surgery may be an effective option for IOP control in aniridic glaucoma patients following a previous failed angle surgery.

A study of mydriatic effect on intraocular pressure and anterior chamber angle morphology by anterior segment optical coherence tomography

Context Pharmacological mydriasis possibly is associated with intraocular pressure (IOP) rise and anterior chamber angle changes. Hence, this study is focused on pressure analysis with anterior segment optical coherence tomography measurements of angle parameters during various dilation phases. Aims Purpose is to investigate IOP variations during dilation phases and to discover association of anterior segment optical coherence tomography measurements. Settings and design Observational study. Patients and methods Thirty-two participants were recruited and IOP measured by rebound tonometer in pre, mid, and full pupillary dilation phases. Lens vault (LV at horizontal and vertical), angle opening distance (AOD at 500 and 750 μm) and trabecular iris space area (TISA at 500 and 750 μm) in temporal and nasal scans were quantified. Paired t test performed to establish a statistical significance P value less than or equal to 0.05. Statistical analysis used MS Excel. Results A total of 32 participants with mean age of 47.5±10.94 years consisting of 17 (53.13%) males and 15 (46.87%) females with 20 (62.5%) right and 12 (37.5%) left eyes were investigated. Mean IOP in pre, mid, and full-dilation phases were 14.86±2.87, 15.94±2.72, and 15.63±2.69 mmHg. Predilation IOP with IOP in mid and full dilation showed statistical significance (P=0.0001, 95% confidence interval 0.56–1.56) and 0.88 and 0.85 Pearson’s coefficients, respectively. IOP analysis with LV, AOD, and TISA in pre, mid, and full-dilation phases exhibited a significant difference (P&lt;0.0001). Conclusion This research highlights an increase in IOP alongside a noteworthy decrease in the average LV by 30.94 μm during mid-dilation compared to the predilation phase. Likewise, the AOD at 750 μm demonstrated a significant reduction by 0.40 and 0.45 μm in temporal scans during mid and full dilation, respectively, while TISA remained unchanged.

Performance of anterior segment OCT-based algorithms in the opportunistic screening for primary angle-closure disease

PurposeThis study aimed to investigate the performance of deep learning algorithms in the opportunistic screening for primary angle-closure disease (PACD) using combined anterior segment parameters. MethodsThis was an observational, cross-sectional hospital-based study. Patients with PACD and healthy controls who underwent comprehensive eye examinations, including gonioscopy and anterior segment optical coherence tomography (ASOCT) examinations under both light and dark conditions, were consecutively enrolled from the Department of Ophthalmology at the Beijing Tongren Hospital between November 2020 and June 2022. The anterior chamber, anterior chamber angle, iris, and lens parameters were assessed using ASOCT. To build the prediction models, backward logistic regression was utilized to select the variables to discriminate patients with PACD from normal participants, and the area under the receiver operating characteristic curve was used to evaluate the efficacy of the opportunistic screening. ResultsThe data from 199 patients (199 eyes) were included in the final analysis and divided into two groups: PACD (109 eyes) and controls (90 eyes). Angle opening distance at 500 μm, anterior chamber area, and iris curvature measured in the light condition were included in the final prediction models. The area under the receiver operating characteristic curve was 0.968, with a sensitivity of 91.74 % and a specificity of 91.11 %. ConclusionASOCT-based algorithms showed excellent diagnostic performance in the opportunistic screening for PACD. These results provide a promising basis for future research on the development of an angle-closure probability scoring system for PACD screening.

A comparison of Scansys and Sirius tomography in healthy eyes

PurposeTo assess the level of agreement and evaluate the reliability of measurements between two Scheimpflug imaging modalities, Scansys (MediWorks, China) and Sirius (CSO, Italy), in quantifying the anterior segment parameters in healthy eyes.MethodsIn a cross-sectional study, the right eyes of 38 healthy participants without any ocular or systemic diseases were examined. A range of anterior segment parameters including anterior and posterior flat and steep keratometry, central corneal thickness (CCT), thinnest corneal thickness (TCT), anterior chamber depth (ACD), anterior chamber angle (ACA), corneal volume, anterior chamber volume, and horizontal white to white diameter, derived from the sagittal curvature maps were measured. To evaluate the reliability of the measurements, intraclass correlation coefficient (ICC) and correlation coefficient were measured. Additionally, Bland-Altman plots were employed to examine the agreement in mean (bias line) and 95% limits of agreement between the two devices.ResultsThe mean age was 31.5 ± 6.9 (range: 19–47) years. The ICC indicated that the majority of anterior segment parameters had an excellent or good level of reliability, surpassing the threshold of 0.9. Nevertheless, CCT and ACA exhibited a moderate level of reliability, with ICC values of 0.794 and 0.728, respectively. The correlation analysis showed a strong correlation for all the variables tested. The Bland-Altman plots revealed that the bias line was near zero and the 95% limits of agreement were narrow for most variables, except for the anterior flat and steep keratometry, which were found to range from − 0.57 to 0.84 D and − 0.68 to 0.87 D, respectively.ConclusionScansys and Sirius devices can be effectively used interchangeably for the evaluation of most anterior segment parameters; however, for anterior corneal curvatures, CCT and ACA, their alternative use is not recommended.

Estimation of angle parameters by ASOCT and biometric parameters by optical biometer in eyes with occludable angles and open angles.

To compare anterior chamber angle (ACA) parameters measured by Anterior Segment Optical Coherence Tomography (ASOCT) and biometric parameters measured by Swept-Source (SS) OCT-based biometry among patients with suspected occludable angles and open angles. An analytical, cross-sectional study was performed on subjects attending our ophthalmology outpatient department with suspected occludable angles (van Herick grades 0, 1, and 2) in group 1, and with open angles (van Herick grades 3 and 4) in group 2. Each subject underwent a complete ophthalmic examination to exclude any intraocular pathology like cataract. We recruited 128 eyes of 64 subjects, 34 in group 1 and 30 in group 2. Each eye was henceforth subjected to ASOCT (Spectralis, Heidelberg Engineering, Heidelberg) and SS-OCT-based optical biometry (IOL Master 700, Carl Zeiss Meditec AG). Anatomical parameters were recorded and compared between the two groups. The main outcome measures of the study included nine ASOCT parameters (central corneal thickness [CCT], lens vault, AOD750, ACA, TISA750 [nasal and temporal], and ACW) and five optical biometric parameters (CCT, ACD, WTW, LT, and axial length). We found a significant difference (p < 0.05) among all the anatomical parameters between the two groups, except CCT which was not significantly different (p = 0.297). ASOCT and SSOCT biometry overcome the challenges of gonioscopy and allow screening for angle closure disease in otherwise normal subjects. ASOCT may serve as an alternative to gonioscopy as it clearly separates occludable angles from open angles in a non-invasive and objective manner.

Effects of crystalline lens rise and anterior chamber parameters on vault after implantable collamer lens placement.

To analyze vault effects of crystalline lens rise (CLR) and anterior chamber parameters (recorded by Pentacam) in highly myopic patients receiving implantable collamer lenses (ICLs), which may avoid subsequent complications such as glaucoma and cataract caused by the abnormal vault. We collected clinical data of 137 patients with highly myopic vision, who were all subsequent recipients of V4c ICLs between June 2020 and January 2021. Horizontal ciliary sulcus-to-sulcus diameter (hSTS) and CLR were measured by ultrasonic biomicroscopy (UBM), and a Pentacam anterior segment analyzer was used to measure horizontal white-to-white diameter (hWTW), anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV), CLR, and postoperative vault (Year 1 and Month 1). The lens thickness (LT) was determined by optical biometry (IOL Master instrument). The predictive model was generated through multiple linear regression analyses of influential factors, such as hSTS, CLR, hWTW, ACD, ACA, ACV, ICL size, and LT. The predictive performance of the multivariate model on vault after ICL was assessed using the receiver operating characteristic (ROC) curve with area under the curve (AUC) as well as the point of tangency. Average CLR assessed by UBM was lower than the average value obtained by Pentacam (0.561 vs. 0.683). Bland-Altman analysis showed a good consistency in the two measurement methods and substantial correlation (r = 0.316; P = 0.000). The ROC curve of Model 1 (postoperative Year 1) displayed an AUC of 0.847 (95% confidence interval [CI]: 74.19-95.27), with optimal threshold of 0.581 (sensitivity, 0.857; specificity, 0.724). In addition, respective values for Model 2 (postoperative Month 1) were 0.783 (95% CI: 64.94-91.64) and 0.522 (sensitivity, 0.917; specificity, 0.605). CLR and anterior chamber parameters are important determinants of postoperative vault after ICL placement. The multivariate regression model we constructed may serve in large part as a predictive gauge, effectively avoid postoperative complication.

ASSESSMENT OF ANTERIOR CHAMBER ANGLE ON ANTERIOR SEGMENT OPTICAL COHERENCE TOMOGRAPHY IN PATIENTS WITH ANGLE CLOSURE GLAUCOMA AND ANGLE CLOSURE SUSPECTS

The objective of this cross-sectional study was to determine the anterior chamber angle using anterior segment optical coherence tomography (AS-OCT) in patients diagnosed with angle closure glaucoma and angle closure suspects. The research was conducted at Shaheed Mohtarma Benazir Bhutto Medical University Larkana, spanning from March 3, 2022, to June 30, 2023. Patients meeting the inclusion criteria and diagnosed with primary angle-closure glaucoma (PACG) were enrolled in the study after obtaining informed consent. The procedure, risks, and benefits of the study were explained to the patients before obtaining consent. AS-OCT was utilized to evaluate patients suspected of primary angle closure and those with confirmed primary angle closure. The results revealed a mean age of 56.21 ± 12.31 years among the study participants, with a confidence interval of 55.04 to 57.38. The mean duration of primary angle closure glaucoma was 22.52 ± 10.98 months, with a confidence interval of 21.47 to 23.57. Of the 423 patients included in the study, 219 (52%) were male, and 204 (48%) were female. Primary angle closure suspect and primary angle closure were observed in 47 (11%) and 44 (10%) patients, respectively. In conclusion, older age, higher central corneal thickness (CCT), and shorter axial length or presence of hyperopia were identified as important independent predictors of suspicion of primary angle closure and primary angle closure. These findings underscore the significance of thorough assessment and monitoring of these parameters in patients at risk of angle closure glaucoma.

The Effect of Persistent High Intraocular Pressure Treated by Phacoemulsification Combined with Goniosynechialysis in Eyes with Acute Primary Angle- closure Glaucoma

AIM: To investigate the availability and safety of phacoemulsification combined with goniosynechialysis for patients with persistent high intraocular pressure in acute primary angle-closure glaucoma. METHODS: Retrospective study. The clinical data of 31 patients (31 eyes) with persistent high intraocular pressure of primary angle-closure glaucoma treated in our center from January 2018 to April 2022 were collected. Each patient underwent phacoemulsification combined with goniosynechialysis after removing the cloudy corneal epithelium and recording the best corrected visual acuity(BCVA), intraocular pressure, and the appearance of the anterior chamber All data were analyzed statistically. RESULTS: After surgical treatment, the best corrected visual acuity was 0.70 (0.30, 0.90) 1 week, 0.30 (0.20, 0.50), 1 month, 0.30 (0.10,0.40), 3 months after surgery, and 0.30 (0.20,0.40) at the last follow-up, respectively, and it was significantly higher than preoperative 1.40 (1.10,2.00) (P &lt; 0.01). The intraocular pressure was 16.20 (12.30,19.40) mmHg, 11.90 (10.80,14.20) mmHg, 13.80 (12.10,16.20) mmHg, 0.30 (0.10,0.40) mmHg and 11.70 (10.40, 12.40) mmHg at 1 day, 1week, 1 month, 3 months, and the last follow-up, and were significantly lower than preoperative 38.60(33.90,42.80)mmHg (P &lt;0.01 ). The central anterior chamber depth and anterior chamber angle width were significantly different between pre-operation and each visit time after the operation (P &lt; 0.01). CONCLUSION: Phacoemulsification combined with goniosynechialysis is a safe and feasible method to treat patients of acute primary angle-closure glaucoma eyes with persistent high intraocular pressure, which can reopen the anterior chamber angle, control intraocular pressure, and improve the visual acuity.

Silicone Oil and Intraocular Pressure: Unraveling the Post-Vitrectomy Relationship

Aim of the Study: To assess the potential influence of silicone oil tamponade following vitrectomy on the early elevation of intraocular pressure (IOP), a critical factor associated with the emergence of secondary glaucoma in individuals with proliferative changes in the vitreous and retina.  Subjects and Methodology: This study was carried out in a prospective manner within the Department of Ophthalmology at Katuri Medical College and Hospital from January 2023 to January 2024, lasting for a duration of 1 year. The research involved 110 participants categorized into three groups based on their medical histories. The control cohort, comprising 40 patients, went through vitrectomy with either air or saline solution as a tamponade. The second group, consisting of 40 patients with retinal detachment and proliferative retinopathy changes, have undergone vitrectomy with silicone oil tamponade. The third group, comprising 30 patients diagnosed with diabetic retinopathy, underwent vitrectomy with silicone oil tamponade. This study encompassed the assessment of intraocular pressure’s (IOP) and gonioscopic findings one month before and after vitrectomy for all the participants. The primary focus of the analysis was the comparison of IOP values across the different groups.  Conclusion: The results indicated that there was no statistically notable contrast in intraocular pressure (IOP) values prior to and following the vitrectomy procedure within the control group (p=0.104). Additionally, there was no substantial difference in preoperative IOP values among the three groups of patients. However, a noteworthy distinction in IOP values was observed during one-month post-vitrectomy, particularly in patients who underwent silicone oil tamponade. This suggests that the use of silicone oil tamponade had a notable impact on intraocular pressure in these patients after the surgical procedure. The study observed that, a month Following vitrectomy, the mean intraocular pressure (IOP) values in individuals with silicone oil tamponade were notably elevated in comparison to the control group (p&lt;0.05). However, when examining individuals with retinal detachment and individuals with diabetic retinopathy changes, did not exhibit a statistically notable variance in IOP one-month post-vitrectomy (p=0.331). Nevertheless, the qualitative examination exposed a 2 mmHg increase in intraocular pressure (IOP) in the diabetic retinopathy cohort. This study indicates that there exists no significant variance in angle width prior to and following vitrectomy among various groups included. Silicone oil in emulsified form was identified in 18% of the individuals with retinal detachment and in 17% of those with diabetic retinopathy, found in the chamber angle. Moreover, within the cohort of individuals with diabetic retinopathy, 10% of patients demonstrated this attribute of angle neovascularization one-month post-vitrectomy. The rise in intraocular pressure (IOP) in the initial postoperative phase can be linked to the introduction of silicone oil into the vitreous cavity following vitrectomy. The emulsification of silicone oil might be a factor in the early elevation of intraocular pressure (IOP), particularly in individuals with diabetes exhibiting angle neovascularization, potentially hastening the development of secondary glaucoma.

Comparative analysis of the anterior chamber changes after intravitreal injections of aflibercept and brolucizumab

BACKGROUND: Currently, the information is insufficient about the effect of multiple intravitreal injections (IVI) of brolucizumab in comparison with aflibercept on the parameters of iridolenticular diaphragm. AIM: The aim of this study is using optical coherence tomography of the anterior segment (AS-OCT) to evaluate changes in the parameters of the anterior chamber in patients with multiple intravitreal injections of aflibercept and brolucizumab in the treatment of the neovascular form of age-related macular degeneration (nAMD). MATERIALS AND METHODS: In total, 60 patients (60 eyes) were included into the study. The follow-up period duration was 12 months. Patients were divided into 2 groups: group 1 — 30 patients receiving intravitreal injections of aflibercept, group 2 — 30 patients receiving intravitreal injections of brolucizumab. Using a Revo NX tomograph, AS-OCT was performed, the depth of the anterior chamber and the dimensions of the anterior chamber angle were examined. The measurement was performed before intravitreal injections, one month after the first, one month after the third intravitreal injections, and one year after treatment. RESULTS: In both groups, a shift of the iridolenticular diaphragm was noted according to AS-OCT data — a significant decrease in depth of the anterior chamber, anterior chamber angle parameters before treatment and after 4 months of treatment, as well as after a year of treatment. In group 1, in contrast to group 2, a greater number of intravitreal injections led to a greater decrease in the depth of the anterior chamber (rxy = 0.415, p = 0.02) and to a greater narrowing of the anterior chamber angle on the nasal and temporal sides (rxy = 0.37, p = 0.049 and rxy = 0.424, p = 0.02, respectively). CONCLUSIONS: For the first time, changes of the anterior chamber of the eye were determined against the background of multiple intravitreal injections of aflibercept and brolucizumab in the treatment of the neovascular form of age-related macular degeneration using AS-OCT.

Anterior Segment Biometry During Accommodation After Posterior Chamber Phakic Implantable Collamer Lens Implantation.

To evaluate the dynamic changes in anterior segment parameters during accommodation following Implantable Collamer Lens (ICL) implantation with swept-source optical coherence tomography (SS-OCT). Under the accommodation of 0.00 diopters (D), 3.00 D, and maximum amplitude, SS-OCT was used to examine the anterior segment parameters, including ICL vault, ICL depth (the distance between the corneal endothelium and the posterior surface of ICL), crystalline lens thickness, anterior chamber depth, and various parameters of the anterior chamber angle, comprising angle opening distance, angle recess area, trabecular iris space area, and trabecular iris angle. During accommodation, the ICL vault showed a significant decrease from baseline (536 ± 278 μm) to 3.00 D (522 ± 281 μm), followed by an increase from 3.00 D to maximum amplitude (548 ± 306 μm) (analysis of variance [ANOVA], P < .001). Four eyes (2.61%) exhibited a decrease in ICL vault to less than 100 μm (47 ± 32 μm) at maximum accommodation. The ICL depth decreased significantly as accommodation increased (ANOVA, P < .001). Crystalline lens thickness increased, whereas anterior chamber depth decreased during accommodation (ANOVA, P < .001). The anterior chamber angle widened during 3.00 D of accommodation but narrowed at maximum accommodation, leading to significant changes in the angle opening distance, angle recess area, trabecular iris space area, and trabecular iris angle during accommodation (ANOVA, P < .001 for all). The anterior segment, including ICL vault and anterior chamber angle, undergo significant dynamic changes during accommodation. These accommodative changes may require careful monitoring for the surgery design of ICL implantation. [J Refract Surg. 2024;40(3):e164-e172.].

Longitudinal Rates of Change in Structural Parameters of Optical Coherence Tomography in Primary Angle Closure Glaucoma following Laser Iridotomy along with Peripheral Iridoplasty.

This study aimed to investigate longitudinal rates of change (LRCs) of structural parameters from optical coherence tomography (OCT) in patients with primary angle closure glaucoma (PACG) after laser iridotomy (LI) along with laser peripheral iridoplasty (PI). Among 146 patients diagnosed with PACG, thirty-two subjects (32 eyes) who underwent LI plus PI and accomplished more than five times of reliable OCT tests were included in the current retrospective study. Retinal nerve fiber layer (RNFL) and Bruch's membrane opening-minimum rim width (BMO-MRW) were measured by spectral-domain OCT with three month interval. LRCs of global and six Garway-Heath sectors were investigated using the linear mixed-effects model which adjusted BMO area, sex, and age. Imaging of dual Scheimpflug analyzer was performed before and at 1 week after LI with PI and yearly thereafter. The mean follow-up period was 32.28 ± 13.34 months with a mean number of 10.18 ± 3.33 OCT images. Baseline characteristics are as follows: age, 63 ± 7.9 years; female, 62.5%; intraocular pressure(IOP), 15.48 ± 4.79 mmHg; anterior chamber depth, 2.09 ± 0.18 mm; and mean deviation, -7.97 ± 8.48 dB. Global LRC of BMO-MRW was 0.86 ± 1.34 μm/yr and RNFL was -0.64 ± 0.22 μm/yr. IOP decreased significantly to 13.06 ± 2.21 mmHg (p=0.001) while anterior chamber volume (p=0.011) and mean anterior chamber angle (p=0.022) increased significantly after LI along with PI compared to the baseline at the final visit. LRC of a new parameter, BMO-MRW, and LRC of RNFL were relatively low in patients with PACG, following LI along with PI. After widening of the anterior chamber angle and decrease of IOP due to LI plus PI, PACG might show stable structural prognosis assessed by OCT.

Direct observation and measurement of circumlental space and its relation to anterior chamber angle characteristics in iridotomized phakic eyes with primary angle closure disease

Primary angle closure disease (PACD) is a major cause of blindness worldwide. It has a high prevalence in East Asia, especially in China, which leads to a higher incidence of blindness than open-angle glaucoma. The aim of this study was to directly observe the circumlental space (CLS) in laser peripheral iridotomized eyes with PACD and to determine whether this structure plays a role in the pathogenesis of PACD. Fifty eyes of 50 patients with PACD, who had received laser peripheral iridotomy performed with neodymium:yttrium–aluminum-garnet were recruited from glaucoma clinics from March 2021 to May 2022, including 17 primary angle closure suspect (PACS), 16 primary angle closure (PAC) and 17 primary angle closure glaucoma (PACG). They were classified into two groups based on whether the ciliary process and the crystalline lens equator were in contact using slit-lamp photograph: the attached group and the unattached group. The demographic, clinical characteristics and anterior segment parameters measured from ultrasound biomicroscopy were compared between the attached group and the unattached group. Thirty-three eyes were assigned to the attached group and 17 eyes belonged to the unattached group. In the unattached group, the mean CLS was 0.10 ± 0.07 mm. No significant differences were identified between the different diagnosis groups in age, sex, best-corrected visual acuity, intraocular pressure, white-to-white, axial length, central corneal thickness, anterior chamber depth, flat keratometry, steep keratometry or iridotomy diameter (p > 0.05). The unattached group had shorter trabecular-ciliary process distance (p = 0.021) and larger ciliary process area (p = 0.001) compared with the attached group. Small CLS and its potential effect (partial ciliary block) might be considered as one of the mechanisms of PACD.

Influencing factors comparing different vault groups after phakic implantable collamer lens implantation: review and meta-analysis

BackgroundStudies on the factors affecting vault after posterior chamber phakic Implantable Collamer Lens (ICL) have been carried out, but most of them are single-centered and subjective selections of parameters. The present study aimed to systematically analyze the factors for vault.MethodsA systematic review of case series, case-control, and cohort studies derived from the articles published in PubMed, the Cochrane Library, Embase, Web of Science, CNKI, CBM, Wanfang and VIP, as well as ClinicalTrials, which were conducted to search for studies on factors of vault using four core terms: phakic intraocular lenses, vault, risk factor and observational study, from January 01, 1997, to February 20, 2023. The included studies were meta-analyzed quantitatively and described qualitatively. Subsequently, meta-regression and subgroup analysis were used.ResultsWe identified 13 studies (1,607 subjects), and 14 factors were considered. Meta-analysis showed that anterior chamber depth (ACD), horizontal corneal white-to-white (hWTW), ICL-size, and age are dual effects of the abnormal vaults; anterior chamber volume (ACV) and lens thickness (LT) are a one-way effect; while axial length (AL), ICL- spherical equivalent (ICL-SE) and Km are insignificant. In addition, descriptive analysis of anterior chamber angle (ACA), horizontal sulcus to sulcus (hSTS), ciliary processes height (T value), crystalline lens rise (CLR), and gender showed that all factors except gender tend to have significant effects on vault. Sensitivity analysis showed stable combined results. Country and design respectively affect the heterogeneity in ACD and ICL-size at low vault, while design affects the heterogeneity in ACD at high vault. No publication bias exists.ConclusionsVault after ICL is related to multiple factors, especially anterior segmental biologic parameters, and they are weighted differently. We hope to provide a reference for the selection and adjustment of ICL.